Apparatus for withdrawing knit work from circular knitting machine

ABSTRACT

Apparatus for withdrawing knitwork from a knitting machine having a needle cylinder. A first conduit including a basket providing a passage for the knitwork axially of the cylinder and a second conduit for passage of the knitwork including means for receiving the knitwork in a perpendicular direction. The first and second conduits intersecting in a plenum chamber having pivotable flap means by which the direction of knitwork movement can be controlled. In one form the basket is provided with axial ducts allowing passage of the air which simultaneously draws the knitwork. In another form the basket is provided with holes to do the same. Air means are provided for selectively moving the knitwork in one or the other direction on pivoting of the flap. The first and second conduits intersecting in a plenum chamber having pivotal flap means by which the direction of knitwork movement can be controlled.

Unlted States Patent 1 [111 3,906,751 Chladek Sept. 23, 1975 [5 APPARATUS FOR WITHDRAWING KNIT 3,426,552 2/1969 Baird 7. 66/149 R WORK FROM CIRCULAR KNITTING FOREIGN PATENTS OR APPLICATIONS MACHINE 955,184 4/1964 United Kingdom 66/149 S [75] Inventor: Otokar Chladek, Trebic,

Czechoslovakia Primary Examiner-W. C. Reynolds [73] Assignee: Elitex, avody textilniho strojirenstvi, Assistant ExammerA' Fahk generalni reditelstvi, Liberec, Czechoslovakia [57] ABSTRACT Filed June 9 1972 Apparatus for withdrawing knitwork from a knitting Appl. No.2 261,549

machine having a needle cylinder. A first conduit including a basket providing a passage for the knitwork axially of the cylinder and a second conduit for passage of the knitwork including means for receiving the knitwork in a perpendicular direction. The first and second conduits intersecting in a plenum chamber having pivotable flap means by which the direction of knitwork movement can be controlled In one form the basket is provided with axial ducts allowing passage of the air which simultaneously draws the knitwork. In another form the basket is provided with holes to do the same. Air means are provided for selectively moving the knitwork in one or the other direction on pivoting of the flap. The first and second conduits intersecting in a plenum chamber having pivotal flap means by which the direction of knitwork movement can be controlled.

7 Claims, 10 Drawing Figures US Patent Sept. 23,1975 Sheet4 Of4 3,906,751

ll lllllllll IIIIJ APPARATUS FOR WITHDRAWING I KNITwoRK v :FROM CIRCULAR:KNITTIN G-MACHINE BAc kGRouNDfo F ,TIIEJINvE TIoN T The present invention relates ito a knitting machine which is providedwith a withdrawing device and a conplane of the'needlecylinder. V

Devices for conveying knitwork under air flow are known. Insuch machines the knitwork is suc'ked ou't of the machine by a tube connected to the needle cylinder. At the opposite end of the tube a mouth is provided 'witha flap and a mesh.-.After'separating the knit work from the needles, the knitwork is sucked in the mouth on to the mesh. After interrupting suction by means of the flap, the underpressure of air is interrupted and a flap at the mouth is opened and the work falls into thecollecting vessel. i

In knitting machines which are provided with only a mechanical withdrawal, or a mechanical withdrawal together with blowing yarninto the needle hooks, a vessel is mounted below the needle cylinder, into which the knitted goods :falls by their own weight, or by their own .weight together with simultaneous effect of air pressure. 1" The disadvantage of the first device consists in that aconsiderable tube lengthlin a large built-up area is created. This results in a substantial tendency to damage the knitwork during transport. It is also difficult to manufacture the tube. Furthermore, the tube is not suitable for co-operation with a rotary catching basket, in which the knitted goods are received after withdrawal from the suction openings. Such a basket must be dismounted and cleaned. I

The disadvantage of the second device consists in that the operators removing the knitted goods from the knitvessel must stoop very lowyparticularly in the case of short knitted goods which completely fill up the vessel. It isan object of the present invention to provide a device which substantially removes the above mentioned disadvantages. I 7

SUMMARY OF INVENTION charge of the knitwork in an opposite or perpendicular direction. Air means are provided for selectively changing the'movement of the knit goods Full details of the present invention together with fur- 1 veying devicefor the knitwork from theknocking-over ther objects and advantages are set forth in the follow-.

ing disclosure and in the attached drawings.

In thedrawingst I v g FIG. 1 is .a.view ofthebottom part of the knitting machine which, is. provided with afan, with the operative.

parts of the device in section,-,the separate elements being in that position, at which the knitwork issuckedoff into the rotary basket.

FIG. 2 is the same deviceas shown in "FIG. lfwi'thl that difference that the separate elements are in a position in which the'knitwork is blown out o'f the rotary basket into the collecting vessel;

FIG. 3 is the same device as shown in FIG. 1, with that difference that the'knitting machine is provided with a mechanism for blowing yarns into needle hooks bymeans of pressure air and a not shown mechanical withdrawing mechanism; j

FIG. 4 is the same view as FIG. 3, with that difference that the separate elements are in a position in which the kn itwork is blown out by means of pressure air from the rotary "basket into the collecting vessel;

"FIG. 5 is a view'inthedirection from the needle cylinder towards the rotary basket on to the section AA as shown in FIG. 1; I

F IG. 6 is aperspective view in the direction of arrow S from FIG. 2 on to the headpiece;

FIGS. 7 and 8 are other constructions of the box with two flaps, FIG. 7 representing said flaps at a position, at which the knitwork moves from the needle cylinder into the rotary basket, while FIG. 8 represents the flaps at a posit-ion at which the knitwork moves from the rotarybasket in the direction out of the machine. FIG. 9 is an axial section of the rotary basket; and FIG. 10 is an axiometric perspective view of the rotary basket.

DESCRIPTION OF INVENTION Turning-to: FIGS. l and 2, the base frame 1 of the knitting machine is provided with a horizontal shelf or flange 2 on which a hollow L-shaped air plenum box 3 is mounted, by conventional means. A horizontal pivot axle 4, running transversely to the flange 2 mounts an arcuately shaped flap 5 which is adapted to swing with aIarge-arc. Leading from the end of the long hollow arm 3a of the plenum box 3 is an air duct headpiece 6 having, as is seen more clearly in FIG. 6, a plurality of vertical louvers 6a at. its outward end and a transverse discharge chute 6b. A cylindrical tube 7 is mounted on the upper wall 3b of the plenum box coaxially with the axis of rotation of the needle cylinder 7,. The tube 7 is mounted so that it is sealed in air tight condition with the box. The needle cylinder 7 is provided with needle beds 7 ;The-knock-over plane of the needle cylinder isin'dicated in-the drawings by the upper edge of the tube 7. A rotating basket 8'which is housed in an enclosed chamber'is mounted coaxially with the tube 7, depending into the base frame 1. The basket 8 has an open upper end which is set below the bottom wall 3C ofithe plenum box and the flange 2. Its lower end is supported in an annular flange 9, secured in the outer race of an annular radial thrust bearing 10. The lower end of thebasket 8 is open so that air passes axially through the basket and debouches into a discharge pipe '11 extending through the radial bearing 10. The pipe 11 is secured against rotationby at least one rod 12 which extendsto the frame 1 'of the machine. A spring 13 is interposed between the end of the rod 12 and the frame 1. The upper end of the cylindrical basket is provided with an annular gear wheel 14, which rests on the flange 2, and which meshes with a drive gear 14a which is connected-by suitable conventional gear train, belt drive or similar means to the needle cylinder directly or tothemain drive or motor of the knitting machine. The connection is such that the basket 8 is made to rotate at the samerate of. speed as the needle cylinder, thus having the same R.P.M.

A hose 15 is connected to the pipe 11 and leads to acircular slide valve 16. The slide valve has an inlet/- outlet to which a conduit 17a is connected leading to the suction side of a fan, compressor turbine or other source of air. The valve 16 has a second inlet/outlet connected by a second conduit 17b to the pressure side of the air source 18. The valve 16 also has an outlet/inlet to atmosphere. A rotatable flap 19 is mounted about a central axle 16a within the valve, which axle 16a'has a lever 20 fixed to it exteriorly of the valve. The lever 20 is connected by a tie rod 21 to one arm of a bell crank lever 22 having a cam finger 22a which bears against a circumferential cam segment 23 mounted on the surface of rotary cam control drum 24. The bell crank 22 is pivoted about a pin 22b and its other arm is connected by a tie rod 25 to a lever 26 which is fixed to the pivot axle 4 by which the flap 5 in air plenum box 3 is controlled.

The rotary basket 8 is seen in detail in cross section in FIG. 5, in axial secion in FIG. 9 and in perspective in FIG. 10. The outer circumference of the basket 8 is generally cylindrical, having eight radially extending spokes 27 in each of which a vertically extending channel 28 extends from the top to the bottom of the basket. The upper or flange end of the basket 8 is open in the same form as the cross-section seen in FIG. 5. The lower end 29 of each channel 28 opens into the pipe 11 at the bottom of the basket and thus air is permitted to flow through channel 28. The lower ends 29 of each channel 28 is bent inwardly toward each other to provide a conical bottom constricted opening over the pipe 11. A ball 30 rests upon the ends 29 and is freely movable within the basket. The gear wheel 14 may be provided with a central hole keyed to the shape of the basket and fixed to the basket by a plurality of horizontally disposed screws. The gear wheel too is provided with threaded holes for the screws, situated in opposite relation to the holes in the basket. The screw heads are countersunk in the basket so as not to hamper the passage of the knitwork.

In operation, the knitwork indicated by the numeral 31 is knit in the usual manner, on the needle cylinder and descends through the cylinder tube 7, the plenum box 3 into the basket 8 which forms a first conduit for withdrawal of the knitwork where it rests on the ball 30 during knitting. As seen in FIG. 9 the knitwork being withdrawn fills the interior of basket without extending into the spokes 27, although they abut against the faces of the channel ribs. This leaves the channels 28 free for passage air in the direction of arrows. As seen in FIG. 1, the air originates in the needle cylinder and moves through the open top end of the channel 28 and then through the bent bottom ends of channels 28 into the duct 11. The air moves around the knitwork in the basket from the plenum 3 to the duct 11, withdrawing the knitwork from the knitting cylinder, after which the knitwork falls into the basket. Simultaneously, air passes between the spokes 27 and the ball 30 out of the basket sucking the knitwork down on to the ball. After knitting the knitwork 31 is moved through the plenum box 3, which forms a second conduit for withdrawal of the knitwork, the headpiece 6, through the discharge chute 6b into a receiving container 32 removably mounted on the machine frame 1. The controldrum may be independently operated or it may also be linked to the rotation of the needle cylinder.

When the knitting machine is provided with a source of pressurized air supplying the needle cylinder so that the yarns are blown onto needle hooks, then the rotary basket 8 is provided with circumferential openings 33 and 34 at the'lower and upper ends respectively. This modified form is seen in FIGS. 3 and 4. The bottom of the rotary basket 8 has a depending annular flange 35 on which the outer ring of a radial thrust bearing 36 is mounted. The inner race is contiguous with an inlet pipe 37. The inlet pipe 37 is similar to the pipe 11 seen in FIG. 1, except that it is of smaller diameter. The pipe 37 is secured against rotation by the combination of rod 12 and spring 13. A narrow hose 38 connects the tube 37 to a variable valve 39 which is controlled by a finger 39a riding on a circumferential segment 23a arranged on the surface of the control drum 24. The valve 39 is connected by a conduit 40 to a second valve 41 also controlled by a finger 41a by the segment 23a. The valve 41 is connected at the end of the conduit 40 to a nozzle 42 arranged along the axis of rotation of the cylinder above knocking-over plane and the tube 7. A T-connection 1 having a conduit 38a is interposed between the valves 39 and 41. The conduit 38a leads to a source of air under pressure, such as a compressor, fan or even an accululator so that pressurized air can be selectively supplied to the basket through hose 38 to blow the knit work out of the basket. The flap 5 is controlled by a single arm lever 43 following the control drum 24 rather than a bell crank. In other respects the apparatus of the embodiment of FIG. 3 is the same as that seen in FIGS. 1 and 2. The flow of air is regulated from the source via the valves 39 and 41 which act in synchronism with the flap 5, through the common control drum 24.

Another embodiment for the plenum box 3 is seen in FIGS. 7 and 8. In this instance two door flaps 5 and 5 are provided. Flap 5 is arranged to move about the pivot axle 4 and is controlled by the lever 26 and tie rod. The flap 5 is flat and is movable to open or occlude only the passage from the tube 7. The second flap 5 is also flat and is pivoted about a second axle 4a at the top wall 3b of the plenum box. The second flap serves only to open or close the passage 3a of the plenum box.

The operation of the device according to FIGS. 1 and 2 of the present invention and the transport of the knitwork 31 from the knocking-over plane of the needle cylinder is as follows:

Upon forming the knitwork 31, the flap 5 is the plenum box 3 and flap 19 in chamber of the slide valve 16 are placed in such a position, as that shown in FIG. 1. The knit-work is consequently sucked by the fan 18 in the direction of arrow P from the knocking-over plane of the needle cylinder via tube 7 and the plenum box 3 and is caught in rotary basket 8, where it is sucked by the air from pipe 11 passing between the radial spokes 27 toward the bottom of the basket. The further downward movement of the knitwork is prevented by the conical seat formed by ends 29 and ball 30 resting thereon, although air continues to move through the basket and the channels 28. There are no means provided to inhibit the knitwork from being introduced or sucked into the channels 28. The knitwork being withdrawn is acted upon only by air pressure acting in the direction of the axis of the passage, so that there exist no lateral forces and, consequently, the knitwork cannot enter the vertically oriented channels 28. As soon as the knitwork starts to accumulate on the bottom of the basket, the air starts to by-pass the knitwork through the channels 28 and a small portion thereof passes through the knitwork itself. The by-passing air urges the knitwork into the channels 28, however, the force of the air acting against the folded knitwork causes no deformation of the latter nordoes it jam the knitwork into the channels, since the knitwork, in its folded state, forms substantially a solidbody and the air has not the necessary force to deform the same- The lifting of the ball 30 upon reversal of the pressure air, depends bothon the force of the pressure air and the weight of the ball. When the ball is light-(made for example of plastic), the initial impact of the reversed air pushesit upwards. However, at the same time the knitwork is removed, and soon after a sufficiently great space for the passage of the air is created and the ball falls down. When the ball is heavy (steel), this phenomenon is not likely to occur.

The continuous vertical channels 27 insure that a constant air pressure acts upon the knitwork 31 during this phase. In a further phase control drum 24 is turned and finger 22a of lever 22 slides down from segment 23 as seen in FIG. 2. This causes the tie rods 21 and 25 to bring the flaps 5 and 19 to the opposite positions in a manner as shown in FIG. 2. Air from the discharge opening of fan 18, which flows through the hose 17b, is then directed through the chamber of slide valve 16 into hose l5 and into rotary basket 8. The knitwork 31 moves by air pressure in the upward direction of arrow P, into headpiece 6, in which it is held by the air pressure louvers 60. Since the ball is freely movable, and air moves through the pipe 11 directly into the basket between the ribs 27, sufficient pressurized air is delivered to blow-off the knit work upwardly. In still a further following phase, the control drum 24 is again turned and finger 22a of lever 22 contacts segment 23 once again. The device is thus returned into its initial position as shown in FIG. 1, releasing the air in the headpiece 6. The knitwork 31 then falls of its own weight, through discharge chute 6b in the direction of arrow P into the receiving container 32.

When the knitting machine is provided with the apparatus according to FIGS. 3 and 4, then its operation is as follows:

Flap 5 (FIG. 3) is initially set in a position, in which the space in the plenum box 3 is uncovered, and knitwork 31 passes in the direction of arrow P into rotary basket 8. Lever 43 rides on the drum 24 sensing the surface of segment 23 aand flap is maintained upon al lowing the knitwork 31 after being knocked-over from the needles to fall by its own weight into rotary basket 8. Openings 34, similarly as openings 33, serve to evacuate air from the basket (FIG. 3). Particularly the openings 34 are designed to permit the air, flowing from the nozzle 42, to escape through them out of the basket when there is a very long knit work in the basket (or a plurality of small ones) and when the layer of the knit work closes the openings 33. If the knitworks 31 ;is unusually long of of a material such as would not fall spontaneously into rotary basket 8, then the knitwork 31 is blown thereinto on the turning of the control drum 24, so that segment 23a opens valve 41 and thus 31 to be removed out of the machines, as shown in FIG.- 4. Simultaneously, segment 23:: contacts feeler of valve 39 and opens it. Pressurized air flows throughhose'38 into rotary basket 8. Then knitwork 31 is discharged in the direction of arrow P into headpiece band remains during the time of action of pressure air caught up on louvers 6a. By further turning of control drum 24, the feeler of valve 39 slides down'from segment 23a and the device is brought to its'initial state as shown in. FIG. 3. The knitwork 31 falls into the collecting basket in the direction of arrow P When arranging box 3 as shown inFIGS. 7 and 8, the operation of flaps 5 and 5 remains the same as that of flap 5. Flap 5 is controlled in the same manner as flap 5. Flap 5 in its position in FIG. 7, is secured by the underpressure of air flowing in the direction of arrow P and its position as shown in FIG. 8 is secured by positive air pressure which flows in the directionofarrow P, or, in a knitting machine provided with a mechanical withdrawing device and pressure air for blowing yarns into needle hooks, this position is fixed by a not shown pawl.

A further modification of design of the device consists in that the headpiece 6 can be dismounted. This modification can be made in machines with a central withdrawing mechanism. Further, instead of rotary basket 8 a stationary basket might be used. Furthermore, basket 8 need not be connected directly to box 3, via a tightly connected air sealed line.

The advantage of the invention as specified above consists in that upon movement of knitwork 31 inside the knitting machine, the possibility of catching knitwork 31 in the basket or the machine is substantially limited and if that situation takes place, it is possible to release the knitwork in a simple manner. The separate parts, i.e. rotary basket 8, box 3, and headpiece 6 are easily dismountable and accessible. Likewise their manufacture, if made of plastic or synthetic material is very easy and economical.

Various modifications and changes are possible. Consequently, the present disclosure is intended to be illustrative and not restrictive of the scope of the present invention.

What is claimed:

1. apparatus for withdrawing and transporting knitwork from circular knitting machine having an axial needle cylinder defining a knock over plane at one end comprising a plenum chamber located below said knock over plane, a first conduit for passage of said knitwork axially arranged with said cylinder and having an upper end below the plenum chamber, means located at the lower end of said first conduit for arresting the passage of said knitwork therethrough, a second conduit for passage of said knitwork intersecting said plenum chamber above said first conduit and arranged transversely of the axis of said cylinder, means for causing a flow of air through said conduits and for selectively changing the direction of said air flow, a flap pivotally mounted within said plenum chamber to selectively occlude one or the other conduits against passage of said knitwork with respect to said knock over plane and means for pivoting said flap.

2. The apparatus in accordance with claim 1 wherein the first conduit comprises a basket, said basket being housed in an enclosed chamber.

3. The apparatus in accordance with claim 1 wherein the means for pivoting said flap comprises a rotary cam about its circumference and a conical bottom having an opening at its center, said source of air being connected to the opening in said bottom, and a ball arranged within said cylindrical basket and adapted to form a seal with the conical bottom for said opening.

6. The apparatus in accordance with claim 5 including means for rotating said basket with respect to said needle cylinder.

7. The apparatus in accordance with claim 1 including means at the end of said second conduit for discharging said knitwork into a receiving receptacle. 

1. APPARATUS FOR WITHDRAWING AND TRANSPORTING KNITWORK FROM CIRCULAR KNITTING MACHINE HAVING AN AXIAL NEEDLE CYLINDER DEFINING A KNOCK OVER PLANE AT ONE END COMPRISING A PLENUM CHAMBER LOCATED BELOW SAID KNOCK OVER PLANE, A FIRST CONDUIT FOR PASSAGE OF SAID KNITWORK AXIALLY ARRANGED WITH SAID CYLINDER AND HAVING AN UPPER END BELOW THE PLENUM CHAMBER, MEANS LOCATED AT THE LOWER END OF SAID FIRST CONDUIT FOR ARRESTING THE PASSAGE OF SAID KNITWORK THERETHROUGH, A SECOND CONDUIT FOR PASSAGE OF SAID KNITWORK INTERSECTING SAID PLENUM CHAMBER ABOVE SAID FIRST CONDUIT AND ARRANGED TRANSVERSELY OF THE AXIS OF SAID CYLINDER, MEANS FOR CAUSING A FLOW OF AIR THROUGH SAID CONDUITS AND FOR SELECTIVELY CHANGING THE DIRECTION OF SAID AIR FLOW, A FLAP PIVOTALLY MOUNTED WITHIN SAID PLENUM CHAMBER TO SELECTIVELY OCCLUDE ONE OR THE OTHER CONDUITS AGAINST PASSAGE OF SAID KNITWORK WITH RESPECT TO SAID KNOCK OVER PLANE AND MEANS FOR PIVOTING SAID FLAP.
 2. The apparatus in accordance with claim 1 wherein the first conduit comprises a basket, said basket being housed in an enclosed chamber.
 3. The apparatus in accordance with claim 1 wherein the means for pivoting said flap comprises a rotary cam drum, and link means connecting said drum and said flap.
 4. The apparatus in accordance with claim 1 including a source of air under pressure and air under vacuum, means for connecting said air under vacuum to said first conduit when said second conduit is occluded and for connecting said air under pressure to said first conduit when said first conduit is occluded.
 5. The apparatus in accordance with claim 4 wherein said first conduit includes a basket comprising a cylindrical body having a conical bottom said basket having a plurality of axially continuous channels arranged about its circumference and a conical bottom having an opening at its center, said source of air being connected to the opening in said bottom, and a ball arranged within said cylindrical basket and adapted to form a seal with the conical bottom for said opening.
 6. The apparatus in accordance with claim 5 including means for rotating said basket with respect to said needle cylinder.
 7. The apparatus in accordance with claim 1 including means at the end of said second conduit for discharging said knitwork into a receiving receptacle. 